Loop taker for sewing machines



g- 1962 R. E. JOHNSON 3,049,086

LOOP TAKER FOR SEWING MACHINES Filed Jan. 25; 1960 2 Sheets-Sheet 1 INVENTOR.

RALPH E. Jam/son! BY WITNESS ATTORNEY Aug. 14, 1962 R. E JOHNSON LOOP TAKER FOR SEWING MACHINES Filed Jan. 25, 1960 Fig. 8

WITNESS 2 Sheets-Sheet 2 INVENTOR.

RALPH E. JOHNSON 2 76 ATTORNEY 3,049,086 LUOP TAKER FUR SEWING MACTHNES Ralph E. lohnson, Mountainside, N.J., assignor to The Singer Manufacturing Company, Elizabeth, N.J., a corporation of New iersey Filed Jan. 25, 1960, Ser. No. 4,387 9 Claims. (Cl. 112-493) The present invention relates to a loop taker for sewing machines and particularly to a rotation restraining means for the thread carrier or bobbin case of a vertical axis oscillating loop taker, which means also serves to hold the thread carrier in operative position in the loop taker and is releasable to provide for removal of the thread carrier from the loop taker.

The object of this invention is to provide, in such a loop taker, a releasable rotation restraining means that is effective and is readily releasable to provide for easy and convenient removal of the thread carrier, is economical, durable and dependable, is easy to assemble, and is adjustable to reduce the required manufacturing tolerances.

Having in mind the above and other objects that will be evident from an understanding of this disclosure, the invention comprises the devices, combinations and arrangements of parts as illustrated in the presently preferred embodiment of the invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings in which:

FIG. 1 is a fragmentary top plan view of a sewing machine hook mechanism embodying the present invention.

FIG. 2 is a vertical sectional view taken substantially on the line 2--2 of FIG. 1.

FIG. 3 is an exploded perspective view of the parts of the hook mechanism of FIG. 1.

FIG. 4 is a View similar to FIG. 1 but with the bobbin carrier removed and the bobbin carrier retaining means in the inoperative position.

FIG. 5 is a top plan view of the bobbin carrier per se.

FIG. 6 is an elevational view of the bobbin carrier per se.

FIG. 7 is a bottom view of the bobbin carrier per se.

FIG. 8 is a detail sectional view taken substantially on the line 8-8 of FIG. 1.

The present invention is illustrated as embodied in the sewing machine that forms the subject matter of the United States patent application of Johnson, Serial No. 4,430 filed January 25, 1960, wherein the machine is fully disclosed and to which reference may be had for a more complete understanding of the machine.

With reference to the drawings, there is illustrated a bed 1 of the frame of a sewing machine. The bed 1 is provided with an integral wall 2 in which is journaled the hook shaft 3 of a vertical axis oscillating a hook indicated generally at 4. Oscillation is imparted to the hook shaft 3 by a crank 5 secured to the lower end thereof beneath the wall 2.

The hook 4 is generally cup-shaped and comprises a ring 6 that is arcuate in cross section and carried by an arm 7 extending from the lower edge of the ring and radially relatively to the hook shaft 3. The arm 7 in effect defines the bottom of the hook 4 which is open except for the arm 7. The ring 6 is open at the top and has an inwardly directed flange 8 that terminates in a free edge 9 which is circular and is disposed concentrically of the axis of the hook shaft 3. The flange 8 is continuous except for a gap formed by a slot 10 cut through the flange 8 from the free edge 9 and into the ring 6, the slot being inclined relatively to a radius from iii-ted rates Patent 9 the axis of the hook shaft 3 to define a loop seizing beak 11 internally of the hook 4.

A thread carrier, or specifically, a bobbin carrier 12 is mounted internally of the book 4 in a manner to provide for oscillation of the ring 6 relatively thereto and for passage of the needle thread loop around the same. The bobbin carrier is formed with an annular Wall 13 that defines a recess or well for receiving a thread carrying bobbin, the wall 13 having an inwardly directed flange 14 at its lower end upon which the bobbin rests. To facilitate removal of the bobbin, there is provided a finger notch 15. Extending from approximately the mid-point endwise or vertically of the wall 13 and substantially normal thereto is an outwardly directed flange 16. To support the bobbin carrier 12 in the ring, there is provided cooperating bearing surfaces between them. Toward this end, there is a peripheral groove 17 formed in the flange 16 and designed to receive the flange 8 of the ring 6, which groove is defined by an upper bearing surface 18 that bears against the upper surface of the flange 8, a lower bearing surface 19 that bears against the lower surface of the flange 8, and a peripheral bearing surface 20 that is formed on a radius complemental to the radius of the free edge 9 of the flange 8 and is in bearing engagement with the free edge 9.

Above the upper bearing surface 18, the flange 16 has an arcuate free edge 21 that is concentric with the ring 4 and terminates over the flange 8 at a point spaced from the free edge 9 thereof. The needle thread loop slides along the edge 21 as it is expanded and thrown about the bobbin carrier by the loop seizing beak 11. Beneath the lower bearing surface 1?, the flange 16 has a free edge 22 that is also concentric with the ring 45 and for clearance is spaced inwardly from the inner surface of the ring 4. The upper limb of the needle thread loop passes over the flange 16 and wall 13 and the lower limb thereof passes beneath the flange 16 and wall 13. The flange 16 is appropriately beveled as at 23 and there is provided beveled surfaces as at 24 and 25 to facilitate the smooth passage of the needle thread. limbs about the bobbin carrier 12.

At its end opposite from the point of loop seizure, the flange 16 has an inclined fiat surface 26 that provides clearance for the thread loop and is designed to receive the loop as it slides off the beak 1 1 at cast-off. Adjacent to the surface 26 the flange 16 terminates in an abutment surface 27. At its end adjacent to the point of loop seizure, the flange 16 is formed with a notch 28 that is bounded at one side by a thread controlling finger 29 and at the other side by an edge including a loop detaining shoulder 39 and an abutment face 31. On the periphery of the wall 13 there is a bobbin thread tension spring 32 secured by a fastening screw 33 and an adjusting screw 34. The free end of the spring 32 has a tab 35 that is received within a hole 36 in the wall '13-. A thread eye 37 through which the bobbin thread emerges is formed in the wall 13 under and adjacent to the free end of the spring 32, a threading slot 38 being provided to facilitate threading the eye 37.

The bobbin carrier 12 is generally semi-circular in shape with an arcuate edge defined by the peripheral bearing surface 20 and a diametrical edge 39 defined by the abutment surface 27, the adjacent edge of the wall 13, and the edge of the thread controlling finger 29. Thus, when in operative position, the bobbin carrier 12 is disposed eccentrically within the ring 6, with the peripheral bearing surface 20 against the free edge 9 and the diametrical edge 39 disposed substantially diametrically of the ring 6. To hold the bobbin carrier 12 in its operative position and to prevent turning of it with the ring 6, there is a bracket 40 mounted on a flange 41 on the top of a bushing 42 in which the hook shaft 3 is journaled.

For securing the bracket 4% on the flange 41, there is a groove 43, formed in the top of the flange that receives a rib '44 on the bottom of the bracket 40, and a screw 45 extends through a bore in the bracket and is threaded into the flange 4-1.

The bracket 40 has an upstanding arm 46 that is adjacent to the point of loop seizure and spaced from the free edge 9 of the flange 8 to provide for needle clearance. The arm 46 terminates beneath the flange 8 except for an upstanding lug 47 that extends into the notch 28 and cooperates with the abutment face 31 to prevent rotation of the bobbin carrier 12 in one direction.

The bracket 40 has a second upstanding arm 48 that carries a platform 49 having a substantially straight face 50 opposed to the diametrical edge 39 of the bobbin carrier 12, an outer edge 51 that conforms to the curvature of the ring 6 and is spaced from the free edge 9 thereof to provide for turning of the ring 6, and an arm 52 extending beyond the face 50. On top of the platform 49 there is mounted an abutment member 53 formed of spring metal and pivotally secured at its rearward end to the platform 49 by a pivot screw 54. The forward end of the abutment member 53 is positioned laterally of the platform 49 by a washer 55 of conventional configuration, i.e., a circular planar element having a central aperture to reduce the same to an annular shape. The Washer 55 is received within a bore 56 in the abutment member and secured to the platform 49 by a screw 57. The central aperture of the washer 55 is enlarged relatively to the shank of the screw 57 so that it can be shifted relatively to the screw, thereby providing for adjustment of the washer in a direction radially of the pivot screw 54 to facilitate manufacture and assembly, and providing for adjustment in a direction normal thereto to align the abutment member 53 with respect to the bobbin carrier 12. The washer 55 is enlarged relatively to the head of the screw 57 so that the head is disposed entirely within the periphery of the washer 55 regardless of the position of the shank of the screw 57 in the central aperture of the washer 55.

The abutment member 53 has a downwardly bent arm 58 that is disposed between the face 50 and the bobbin carrier 12 and serves as a thread guard. The arm 58 has a free end 59 that engages the abutment surface 27 to prevent turning of the bobbin carrier 12 in the direction opposite to the direction in which the lug 47 is operative.

The abutment member 53 is adapted to be lifted off the washer 55 and swung about the pivot screw 54 to move the free end 59 away from the bobbin carrier 12 and thus permit removal of the bobbin carrier 12 from the ring 6. When swung out, the free end 59 is adapted to rest on the arm 52. To return the abutment member 53 to its operative position, it is swung about the pivot screw 54 until it snags over the washer 55.

Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to a preferred embodiment of my invention which is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.

Having thus described the nature of the invention, what I claim herein is:

1. In a sewing machine having a frame, an oscillating loop-taker journaled in said frame and including a ring, a semi-circularly shaped thread carrier disposed eccentrically internally of said ring and defining an open space between said thread carrier and said ring, cooperating bearing surfaces on said ring and said thread carrier for supporting said thread carrier and providing for angular movement of said ring relatively to said thread carrier, and means for holding said thread carrier against turning with said ring and against movement relative to said ring to separate said bearing surfaces comprising a stationary bracket secured in said frame and extending upwardly internally of said ring and in the open space between said thread carrier and said ring, an abutment member, means mounting said abutment member on said bracket for swinging about an axis parallel to the axis of oscillation of said loop taker from an operative position wherein said thread carrier is held against turning with said ring and with said bearing surfaces in engagement and a release position in which said thread carrier is free to be moved relatively to said ring to disengage said bearing surfaces and thereby to permit removal of said thread carrier from said ring and means for releasably holding said abutment member in operative position.

2. In a sewing machine having a frame, a bushing mounted in said frame and having at one end a flange, an oscillating loop-taker having a shaft journaled in said bushing and including a ring disposed adjacent to said flange, a semi-circularly shaped thread carrier disposed eccentrically internally of said ring and defining an open space between said thread carrier and said ring, cooperating bearing surfaces on said ring and said thread carrier for supporting said thread carrier and providing for angular movement of said ring relatively to said thread carrier, and means for holding said thread carrier against tuming with said ring and against movement relative to said ring to separate said bearing surfaces comprising a stationary bracket mounted on said flange and extending upwardly internally of said ring and in the open space between said thread carrier and said ring; an abutment member, means mounting said abutment member on said bracket for swinging about an axis parallel to the axis of oscillation of said loop taker from an operative position wherein said thread carrier is held against turning with said ring and with said bearing surfaces in engagement and a release position in which said thread carrier is free to be moved relatively to said ring to disengage said bearing surfaces and thereby to permit removal of said thread carrier from said ring, and means for releasably holding said abutment member in operative position.

3. In a sewing machine in accordance with claim 2 in which said flange and said bracket are provided with a eomplemental tongue and groove for positioning said bracket on said flange.

4. In a swing machine having a frame, an oscillating loop-taker journaled in said frame and including a ring, a thread carrier disposed internally of said ring, cooperating bearing surfaces on said ring and said thread carrier for supporting said thread carrier and providing for angular movement of said ring relatively to said thread carrier, and means for holding said thread carrier comprising a stationary bracket secured in said frame and extending upwardly internally of said ring and adjacent to said thread carrier, a lug on said bracket, said thread carrier having a notch receiving said lug, an abutment member including a finger adapted to engage said thread carrier and to hold the same against rotation with said ring and against removal from said ring, means mounting said abutment member on said bracket for swinging from an operative position wherein said thread carrier is held against turning with said ring and with said bearing surfaces in engagement and a release position in which said thread carrier is free to be moved relatively to said ring to disengage said bearing surfaces and thereby to permit removal of said thread carrier from said ring, and means for releasably holding said abutment member in operative position.

5. In a sewing machine having a frame, an oscillating loop-taker journaled in said frame and including a ring, a thread carrier disposed internally of said ring, cooperating bearing surfaces on said ring and said thread carrier for supporting said thread carrier and providing for angular movement of said ring relatively to said thread carrier, and means for holding said thread carrier comprising a stationary bracket secured in said frame and extending upwardly internally of said ring and adjacent to said thread carrier, an abutment member formed of spring-like material, means securing said abutment member at one end to said bracket for swinging about an axis parallel to the axis of oscillation of said loop taker from an operative position wherein said thread carrier is held against turning with said ring and with said bearing surfaces in engagement and a release position in which said thread carrier is free to be moved relatively to said ring to disengage said bearing surfaces and thereby to permit removal of said thread carrier from said ring, and positioning means on said bracket for engaging the other end of said abutment member when in the operative position to position said abutment member relatively to said thread carrier, said abutment member being releasable from said positioning means by flexing the engaged end thereof away from said bracket.

6. In a sewing machine in accordance with claim 5, in which said positioning means is adjustable relatively to said bracket to vary the operative position of said abutment member.

7. In a sewing machine in accordance with claim 5, in which said positioning means comprises a washer, means for adjustably securing said washer to said bracket, said abutment member having an aperture for receiving said washer.

8. In a sewing machine in accordance with claim 7, in which said means for adjustably securing said washer to said bracket comprises a screw having a head overlying said washer and a shank extending through a central aperture in said washer, the central aperture in said washer being enlarged relatively to the shank of said screw, said washer being enlarged relatively to the head of said screw so that said head is disposed within the periphery of said washer to permit lifting of said abutment member out of engagement with said washer.

9. In a sewing machine having a frame, a loop taker journaled in said frame for angular movement and including a ring formed with a bearing flange extending inwardly relatively to the axis of said ring and having a gap therein and a loop seizing beak formed on said flange at one side of said gap, said loop taker having during operation a loop seizing position wherein said loop seizing beak enters a loop of needle thread, a thread. carrier disposed internally of said ring, said thread carrier being substantially semi-circular in shape with an arcuate edge and a diametrical edge and being disposed in said ring with one end of said diametrical edge adjacent to said loop seizing position, said arcuate edge having a raceway receiving said bearing flange for providing for angular movement of said ring relatively to said thread carrier, and means for holding said thread carrier against angular movement and against separation of said bearing flange and said raceway to prevent removal of said thread carrier from said ring comprising a stationary abutment lug secured to said frame and engaging said thread carrier adjacent to said loop seizing position, and an abutment member having a resilient arm for engaging said diametrical edge adjacent to the end remote from said loop seizing position, means mounting said abutment member in said frame for pivotal movement from an operative position in which said resilient arm is in engagement with the respective end of said diametrical edge to hold said thread carrier against turning with said ring and with said bearing flange and said raceway in engagement and a release position in which said thread carrier is free to be moved relatively to said ring to disengage said raceway from said bearing flange and thereby to permit removal of said thread carrier from said ring.

References Cited in the file of this patent UNITED STATES PATENTS 678,947 Diehl et al. July 23, 1901 2,544,227 Hohmann Mar. 6, 1951 FOREIGN PATENTS 83,489 Switzerland May 7, 1920 

